In wireless mobile communications systems, the transmitter and the receiver often perform operations to maintain or improve the performance of the communication channel. For example, in a cellular network (e.g., 2G, 3G, 4G, CDMA, GSM, LTE, etc.), the base station and mobile terminals may periodically estimate or measure (or provide data useful estimation of) transmission characteristics of the channel between the base station and the mobile terminal. The obtained channel information may be used to optimize modulation scheme used for transmission, scheduling transmissions over the network, and so on.
However, due to mobility of the transmitter and/or the receiver, channel characteristics measurement may vary rapidly or may be inaccurately measured. This inaccuracy may be partially alleviated by estimating the travel speed of a mobile terminal. Presently available techniques make use of multiple spatially separated antennae to receive signal from a mobile terminal and estimate the speed of travel of the mobile terminal. Some techniques use a priori knowledge of the mobile terminal's travel direction for estimating the rate of travel. Due to various practical reasons, e.g., the presence of multi-path, such speed measurement techniques often provide inaccurate or unsatisfactory results. Therefore, there is a need for improved techniques for estimating speed of a mobile terminal.